Homeowner guide · Montreal

5 questions to ask before you hire

Most duct cleaners in Montreal aren't certified — and even certified companies differ wildly on price, equipment, and who shows up at your door. Use this checklist on every quote call.

5Must-ask questions
2Ways to verify
5 minTo read & use
Smart Consumer — research and verify before you hire a duct cleaner

Don't take marketing at face value. Anyone can say they're "certified" or "professional" on a website. These five questions separate trained, properly equipped companies from the ones you'll wish you hadn't opened the door to — and each one includes what a good answer sounds like.

The checklist

Ask every company the same five questions

Copy this list before your next phone call or quote request. If the answers are vague, keep looking.

Are you certified with NADCA or IAQCert — and can I verify it myself?

Certification proves a company follows industry training standards — but you should never take their word for it. A legitimate company will welcome you checking. This question has two parts, depending on what you find.

IAQCert certifies individual technicians — always ask for their Certificate ID and confirm it online, whether or not the company is a NADCA member.

Verify NADCA membership

Search the company's legal name on NADCA's official directory.

nadca.com/find-a-professional →

Verify IAQCert credentials

Ask the technician for their Certificate ID, then enter it on IAQCert's verification page.

CADCT-089341
iaqcert.com/verify-certificate →
Part 1 · On NADCA

If they're a verified NADCA member

NADCA requires members to carry liability insurance and prove it to the association. If you find them listed on NADCA's directory, that insurance requirement has already been verified — you're in good shape on coverage.

Part 2 · Not on NADCA

If they are not a NADCA member

Ask for proof of liability insurance before you book — especially if they'll be working inside your furnace or on your HVAC system. If something is damaged during the job, you need to know they're properly covered.

A legitimate company will provide a certificate of insurance without hesitation. Don't let an uninsured contractor touch your furnace.

You might wonder

"Does it really matter if they're not certified?"

Yes — it matters a lot. Saving a few dollars on an uncertified company is a gamble most homeowners wouldn't take if they understood what's actually at stake:

  1. Safety first

    Duct cleaning puts technicians inside your furnace — near wiring, motors, gas lines, and heat exchangers. An untrained person can cause a short circuit, damage components, or create conditions that lead to overheating or fire. Certification means they were trained on electrical and HVAC safety, not just how to plug in a vacuum.

  2. Real skill for a genuinely difficult job

    Ducts run between walls, floors, and ceilings — most of your system is completely hidden. Cleaning it properly requires knowing how airflow works, where to access the full run, and how to do it without damaging your home. Untrained crews routinely skip what they can't easily reach.

  3. You can't verify the result yourself

    Nobody can show you a photo of the inside of a duct buried in your wall. You have to trust that the work was done — which means trusting the knowledge and skill of whoever you let in. Certification is one of the few objective ways to know that training was tested, not just claimed on a flyer.

  4. Training has to stay current

    IAQCert and NADCA credentials aren't permanent stickers. Technicians must renew every year — and NADCA members must pass a recertification exam annually. That keeps standards current, not based on a course someone took a decade ago.

  5. The cost of getting it wrong

    If an uncertified contractor damages your furnace, ductwork, or wiring, repair bills can run into thousands — with no guarantee they're insured or accountable. Saving $50 on the quote to hire an unverified company is a bet on your home's safety and your wallet. It's not a smart trade.

Certification isn't marketing fluff. It's proof that someone was trained, tested, insured, and held to a standard — in a trade where you literally cannot inspect most of what they touch.

Good answer

"Yes — search our company name on NADCA. As a member, we carry the liability insurance NADCA requires. Our technicians hold active IAQCert IDs and we'll share them before your appointment."

Red flag

They claim certification but can't tell you how to verify, refuse to provide an IAQCert ID, won't show proof of insurance when they're not on NADCA, or get defensive when you ask.

Is your price a flat rate, or can it change once you arrive?

A trustworthy company quotes a clear flat rate for your home size and system type before anyone steps through your door — including how many vents are included and what each extra vent costs. The price should only change if you choose to add optional services — never because of surprise "discoveries" on arrival.

Good answer

"Your base price is $X for a single-furnace home, plus $Y per supply and return vent. We'll count your vents when we quote so you know the full total before we arrive — no surprises on vent count. Optional add-ons like UV lights or coil cleaning are quoted separately and only done if you approve."

Red flag

"Starting at $99," bait pricing, or technicians who find "extra problems" on arrival and pressure you to pay more before finishing the job.

How many technicians will arrive — and how long will they be in my home?

Proper duct cleaning takes time. For a standard single-furnace home, expect two technicians on site for roughly 2.5 to 4 hours. One person finishing in under an hour usually means registers were wiped — not a full system clean.

Good answer

"Two certified techs. Plan on about 3 hours — we remove every vent cover, clean the full duct run, and service the furnace area."

Red flag

One person, no time estimate, in-and-out in 45 minutes, or they can't explain what they'll actually do while they're there.

What equipment do you use — truck-mounted or portable?

Real duct cleaning requires serious negative-air equipment. The two acceptable setups are a truck-mounted vacuum system or an industrial-grade 220V HEPA portable (built-in, high-performance — not a consumer unit).

If they pull up with a shop vac or a small household portable, send them away. That equipment cannot properly pull debris from your full duct system.

Good answer

"We use truck-mounted negative-air equipment" or "Our 220V HEPA portable is industrial-grade — we'll show you the unit when we arrive."

Turn them away

Shop vac, small consumer portable, or no visible professional vacuum at all. No exceptions.

Will your own staff do the work — or subcontractors?

You're hiring a company — you deserve to know who actually enters your home. Look for uniformed employees, a marked company truck with branding, and company-owned equipment on the truck.

Good answer

"Our own W-2 employees — in company uniforms, in a marked truck, with the company's equipment. The same team you booked is the team that arrives."

Red flag

Unmarked van, no uniforms, different company name on the invoice, or they can't tell you who is coming until the day of the job.

Quick reference

Your 30-second checklist

Before you book, every company should check "yes" on all five.

NADCA verified (insurance already vetted) — or proof of liability insurance if not NADCA
Base price + per-vent cost, with vent count in the quote upfront
Two techs, ~2.5–4 hours for a single-furnace home
Truck-mount or industrial 220V HEPA portable — never a shop vac
Uniformed staff, marked truck, company equipment

How Duct Masters answers

Here's how we answer these five questions.

In business since 2005 · NADCA member since 2014. IAQCert-certified technicians. Flat-rate packages with DustCheck™ on every job. Two techs, truck-mounted equipment, branded uniforms and trucks — no subcontractors, no bait pricing.

Verify us yourself — then compare. We'd rather you hire the right company than the cheapest quote.

These five questions cover the essentials. For a full side-by-side — what Montreal homeowners tell us they've experienced elsewhere vs. how we do it — see The details that actually matter on our homepage.

Why homeowners choose us →

Ready to book with confidence?

Ask us these same five questions — we'll answer every one, and you can verify every claim before we arrive.